arm64 seems quite flaky - used to work, sort of, but now, my build simply
never finshes:
https://travis-ci.org/github/GrokImageCompression/grok/jobs/704649365
I get this message in the console:
sudo: unable to resolve host travis-job-grokimagecompr-grok-704649365: Name or service not known
I was just looking into arm64 as it indeed seems to be faster.
My builds seem to finish, but I do see the ‘sudo’ errors. Apart from the announcement of gravitron2 on the blog, there’s not been a great deal of info on gravitron.
And your message is from a year ago now and today I got the same error messages 
I’m afraid it’s just not really well supported, so I might stick to x86 for now.
Or are there people with great success stories on arm64?